Construction of roofs



(No Model.)

A. MQDOUGALL. CONSTRUCTION OF ROOPS, FLOORS, PAVEMENTS, &c.

m'inedo as.

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Tn: Nonms PETERS-CU, vHoYa-urua, WASHINGTON, a, c.

UNITED STATES ALEXANDER MCDOUGALL,

OF DULUTH, MINNESOTA.

CONSTRUCTION OF ROOFS, FLOORS, PAVEMENTS, 8w.

SPECIFICATION forming part of Letters Patent No. 582,395, dated May 11,1897.

Application filed June 29, 1895. Serial No. 554,470. (No model.)

To all whom it may concern.- Be it known that I, ALEXANDER MCDOU- GALL,a citizen of the United States, residing at Duluth, in the county of St.Louis and State of Minnesota, have invented certain new and usefulImprovements in the Construction of Roofs, Floors, &c.; and I do herebydeclare the following to be a full, clear, and exact description of theinvention, which will enable others skilled in the art to which itappertains to make and use the same.

My invention relates to the construction of roofs, floors, car-tops,streets, pavements, and other flat or approximately flat surfaces,eitherhorizontal, inclined, or vertical, whereby a cheap, rigid, and durablestructure will be obtained.

The methods by which iron and steel are now produced are such that thecost of those commodities has been so reduced as to enable structureswhich are, now built of cheaper materials, such as wood and stone, to bebuilt of the more durable metals mentioned. As the'processes for makingiron and steel are being improved upon all the time, the day does notappear to be far distant when iron and steel will entirely supplant theless durable materials now used in the construction of many forms ofstructures.

By means of my present invention I propose to construct roofs, floors,.and other flat surfaces of iron and steel in such a way that thestructures so built will be possessed of great rigidity and durability,and such structures can be built at a comparatively low cost.

In carrying out my invention in the construction of these structures theiron and steel made use of maybe produced and erected mostly bymachinery, whereby such structures can be economically built, and whenthe durability and rigidity and other advantages are taken intoconsideration will be as cheap, if not cheaper, than when suchstructures are constructed of wood and other less durable materials.

For the better comprehension of my invention attention is directed tothe accompanying drawings, forming a part of this specification, and inwhich- Figure 0 is a side elevation of a portion of a roof constructedin accordance with my invention; Fig. 1, a similar view of a car-top orfloor embodying the same; Fig. 2, an enlarged cross-sectional View ofFigs. 0 and 1; Fig. 3, a side elevation, partly in section, of a streetor sidewalk embodying my invention; Fig. 4, a similar view of a sidewalkor street, showing the use of web-plates; Fig. 5, a cross-sectional viewof Fig. 3; Fig. 6, a cross-sectional view of Fig. 4; Fig. '7, anenlarged section of the joint between the channel-irons of Fig. 5 Fig.8, a similar view of the joint between the channel-irons of Fig. 6, andFig. 9 a similar view of the preferred construction of webplates.

In all of the above views corresponding parts are designated by the sameletters of reference.

The main feature underlying my invention is to construct a flat surfacefor any purpose whatever of a series of channel-irons placed side byside with the flanges of said channelirons riveted, welded, or otherwisesecured together, whereby a perfectly flat surface will be obtained andthe flanges of the channelirons will serve as ribs for offeringlongitudinal support to the structure. In order to further augment thelongitudinal strength of the structure, web-plates maybe placed betweeneach of the abutting flanges and secured in place, or said web-platesmay be secured between alternating flanges or be arranged in any otherway. In all of the views above referred to this general principle iscarried out, only modified more or less to suit the respectiveconditions to which the invention is to be applied.

Referring to Fig. 2, a a a represent a number of ch annel-irons made ofiron or steel and which may be conveniently produced in any suitableform of rolling-machine. These channel-irons are provided at each sidewith a depending flange 1), extending preferably the entire length ofthe channel-iron and are of any suitable depth.

From an inspection of the drawings it will be seen that thechannel-irons which I make use of are comparatively shallow. The depthtoo adjacent channel-irons, and the parts of the structure are thenriveted, bolted, welded, or otherwise secured together. In this way avery durable, light, and cheap structure will be produced for anypurpose whatever.

At the ends of the structure the web-plates are provided with horizontalflanges cl at their lower ends, which flanges may be used to secure thecompleted structure in position. \Vhen the channel-irons a a andweb-plates c are thus set up, they can be used, as shown in Fig. 0, forthe construction of roofs, in which case the web-plates O can beinclined along the bottom edge, so as to allow for the slope or inclineof the roof, or the said web-plates can be of the same depth throughout,as shown in Fig. 1, and secured on inclined stringers or stanchions.Such a structure can also be used in the construction of car tops andfloors, as shown in Fig. 1, and will possess many advantages.

By making a top for cars for carrying gravel, dirt, coal, or otherbulkcargoes a perfeetly flat surface will be produced, from which the loadcan be removed by an automatic unloading apparatus.

Such a structure as I have above described is also well adapted for usein construction of streets and sidewalks, as shown in Figs. 3, 4, 5, and6.

In Fig. 3 I show a sidewalk or street composed of a series ofchannel-irons a, the flanges b whereof are riveted immediately togetherwithout using the web-plates o, as above explained, the structure beingsupported at the side by a continuous stringer 6, having the flange f atthe top, to which the flanges b of the channel-irons a may be riveted,said stringer 6 being riveted to and supported by a horizontalchannel-iron g, which also serves as an effective gutter for carryingoff water which may flow upon the tops of the channel-irons a. In Fig. 4substantially the same construction is shown as j ust explained, exceptthat web-plates 0, such as I have illustrated in Figs. 0, 1, and 2, aremade use of, such webs being cut away at the ends to allow for the useof the longitudinal stringer e.

In Fig. 9 I have illustrated the preferred construction of web-plates c,which is composed, essentially, of a continuous plate having an enlargedbead or head it at its lower end,said bead or head being preferablyformed by rolling the plate at the lower end or in any other way. Bymaking a web-plate of this construction the enlarged bead or head servesmaterially to augment the strength thereof.

lVhile the channel-irons a a are generally of a common construction, yetthey differ in one point from most of the channel-irons which are nowupon the market in that the outer edges -i thereof are formed with aperfect angle, whereby when the channel-irons are abutted together aperfectly flat surface will be obtained. In most of the channelironswith which I am familiar this edge is more or less rounded, so that whenthe channel-irons are placed together longitudinal ridges or grooveswill be formed. Such longitudinal ridges or grooves are notobjectionable, and I may make use of the same without departing from thespirit of my invention, and, in fact, in some instances the provision ofsuch grooves or channels may be of advantage.

Instead of supporting a flat-surface structure in accordance with myinvention on stringers e, as explained, when the same is to be used inthe construction of streets or pavements, it is obvious that the flangesof the said channel-irons or the said web-plates when used may beheldupon orbe embedded in the earth or be supported on a wooden, stone,cement, or other foundation. Channel-irons, as I have explained and asis well known, can be very cheaply formed by machinery, and the rivetingof said channelirons together may be effected by the use of a hydraulicor other power riveter, whereby the setting up of the structure will bevery gradually facilitated.

Instead of riveting the flan ges b of the channel-irons together asstated, it is obvious that said channel-irons may be welded togetherthrough the whole or parts of their lengths, an electric welder beingpreferably used for this purpose.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is as follows:

1. In the construction of streets or pavements, the combination of aseries of channel-irons a having depending flanges b, said channel-ironsbeing arranged side by side With the flanges b rigidly secured together,a longitudinal stringer e at the ends of said structure and to which theflanges Z) are riveted and the horizontal channel-iron g at the lowerend of said stringer c, said chann el-irou g constituting a gutter forthe purpose mentioned, substantially as set forth.

2. In the construction of streets and pavements, the combination of aseries of chaunel-irons 0., having depending flanges 19, webplates 0secured in place between the flanges of adjacent channeLirOns, and thestringer e at the end of the structure for supporting the same, saidweb-plates 0 being cut away at their ends to accommodate said stringers,substantially as set forth. I

In testimony whereof I affix my signature in presence of two witnesses.

ALEXANDER MODOUGALL.

Witnesses:

CHAS. W. LELAND, G. A. LELAND.

